backbone.js - using parse without calling fetch

backbone.js, javascript

Solution

Update: This answer is now out of date, see uglymunky's answer for more up to date information.

You're right, `parse` is only specified to be called during `fetch` so it won't be called when you're building a collection from raw data.

But, since you control the raw data that you're using to bootstrap your collection, you can call your collection's `parse` yourself:

var c = new YourCollection(
    YourCollection.prototype.parse([
        // attribute data goes here...
    ])
);

Demo: http://jsfiddle.net/ambiguous/kdaZ3/

Your `parse` methods (both collection and model) shouldn't care about their calling context so calling them directly from the prototype should be fine.

Problem

On page load I'm bootstrapping my data to my collections via this technique. That works great, but I'm running into an issue where I have sub-models which also need to be cast. For example, I return a JSON collection called Book, and each book array contains 10-20 models themselves called Pages. If I try and access Pages directly, I get the `[object][object]` error as Backbone can't figure out what type of object it is. Previously when I was using `fetch`, I would get around this by using collections which contained a `parse` action. In `parse` I would do something like: ``` Collection_Books = Backbone.Collection.extend({ model: Model_Book, parse: function (response) { response.Pages = new Collection_Pages(response.Pages); return response; } }); ``` Now that I'm accessing the data directly and not using `fetch`, the documentation implies that I no longer have access to the `parse` method. If I am not using `fetch` or calling a server on page load, how can I cast sub-models using the Books > Pages example?

Original source